> On Aug. 6, 2017, 3:17 p.m., Albert Astals Cid wrote:
> > Rasterizing usually makes stuff look quite bad (because the wrong
> > resolution is chosen) , have you tried printing text or things with sharp
> > lines?
>
> Oliver Sander wrote:
> Yes I tried that, and it looks very good. It looks so good I wasn't even
> able to tell that it was rasterized before printing. The resolution chosen
> by the code adapts to the printer
>
> QImage img = pp->renderToImage( printer.physicalDpiX(),
> printer.physicalDpiY() );
>
> and I guess it must be pretty large when printing to an actual printer.
>
> Albert Astals Cid wrote:
> So we will kill cheap printers/computers by using lots of memory? Can you
> try to see how much memory is used printing an A4 page? Also make sure that
> printing N pages doesn't need N times the memory (i guess using heaptrack or
> similar)
>
> Oliver Sander wrote:
> Quick first results: printer.physicalDpiX() returns a value of 1200, both
> for printing to my office printer and for printing to a file. An A4 printout
> results in a 9921 x 14032 bitmap; the corresponding file size is 804 KB
> (greyscale). Testing the actual memory consumption will take me a bit more
> time.
>
> I don't actually care about the exact resolution. If you say "bah, just
> hard-code 72dpi there" that's fine with me.
>
> Albert Astals Cid wrote:
> > 9921 x 14032 bitmap
>
> Does that mean that you need 9921x14032x32 bits in memory? That's around
> 530 MB, right? I guess it's not horrible in todays big scheme of things if it
> doesn't get multiplied by the number of pages.
>
> Oliver Sander wrote:
> I now tried to measure the heap consumptions using valgrind/massif. I
> printed to files exclusively, to save some trees.
>
> If I read the massif output correctly, the new code needs about 1GB of
> heap space to print A4 pages, and that is independent of the number of pages.
>
> On the other hand, printing an A0-size poster fails with the friendly
> message "Bogus memory allocation size". Not really surprising: that would
> need an enormous amount of memory.

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> On the other hand, printing an A0-size poster fails with the friendly message
> "Bogus memory allocation size". Not really surprising: that would need an
> enormous amount of memory.
I'm not sure i'm ok with that.
Why are we discussing this instead of printing pdf directly?
- Albert
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This is an automatically generated e-mail. To reply, visit:
https://git.reviewboard.kde.org/r/130218/#review103569
-----------------------------------------------------------
On Aug. 4, 2017, 8:20 p.m., Oliver Sander wrote:
>
> -----------------------------------------------------------
> This is an automatically generated e-mail. To reply, visit:
> https://git.reviewboard.kde.org/r/130218/
> -----------------------------------------------------------
>
> (Updated Aug. 4, 2017, 8:20 p.m.)
>
>
> Review request for Okular.
>
>
> Repository: okular
>
>
> Description
> -------
>
> When the users chooses to print with rasterization and annotations, it is
> easy to print directly to a QPrinter, rather than converting to PostScript
> and then using CUPS tools. The code for it was already there, but it was
> hidden behind an #ifdef Q_OS_WIN. This patch enables it for all plattforms.
> If nothing else, it will make an interesting debugging tool, because it
> allows to bypass the postscript & cups toolchain from the GUI. This may allow
> to track down some of the numerous my-printer-settings-are-getting-ignored
> bugs.
>
> Incidentally, this patch does fix at least one bug for me: Without it, my
> printer will happily ignore the 'print in grayscale' button. With the patch,
> that button is suddenly honoured.
>
> This patch is a part of https://git.reviewboard.kde.org/r/130055/ . I post
> it here separately because I am not sure anymore whether the other stuff in
> that larger patch is a good idea.
>
>
> Diffs
> -----
>
> generators/poppler/generator_pdf.cpp 42ccb3a26
>
> Diff: https://git.reviewboard.kde.org/r/130218/diff/
>
>
> Testing
> -------
>
> Printed a few test sheets, to a printer and a file.
>
>
> Thanks,
>
> Oliver Sander
>
>